Liquid low-melting eutectic hydroxylammonium acid sulfate composition



United States Patent "ice 3,487,022

Patented Dec. 30, 1969 any minor impurities introduced during the process of 3,487,022 manufacture of the HAS. At 75% HAS, the sulfuric acid LIQUID W- T CTIC H DR content is within the range of from about 5.7% to about AMM NIUM A ID SULFATE COMPOSITION 12.5%, and at 85% HAS, the sulfuric acid content is Wallace F. Runge Terre Haute Ind. assignor to Comb b mercial Solvents Corporati0n, New Y0rk, N.Y., a cor- W1 hm the range of from about 21% to a out 62% y weight. These compositions have crystallization temperagg ggg i g g fig g 31 1966 Ser No. 590 530 tures of about 25 C. or below. Crystallization tempera- Int C09k 3/02 ture is defined as the temperature at which the first crys- U s L 252 133 Claims tals appear, and the solidification temperature is a feW 10 degrees lower.

The HAS-sulfuric acid-water compositions having ABSTRACT OF THE DISCLOSURE crystallization temperatures below about 25 C. are suitble for shipment as liquids in acid-resistant bulk con- Llquid compositlons having from 75% to 85% by Weight of hydroxylammonium acid sulfate, sulfuric acid tamers, 1.e. tank cars and tank trucks, without appreciable and water, and having crystallization temperatures below fi g ggxg zf ggg fss f g' gi gg lz gss 25 bemg especlally Sultable for Shlppmg m bulk trucks, and advantageously can be heated just prior to loading. If the compositions do solidify, they can be easily melted again by heating. The HAS compositions of this s invention relates to hydfoXylammonium d 8111- invention can be handled in bulk by following much the fate compositions. In a particular aspect it relates to same techniques as used for sulfuric acid. These HAS liquid hydroxylammonium acid sulfate compositions suitcompositions are, however, much less hazardous than sulable for transportation in bulk containers. furic acid.

Hydroxylammonium acid sulfate, hereinafter referred The preferred compositions of this invention have crysto as HAS, is useful as a reducing agent and a reagent tallization temperatures below about 20" C. and are espe for synthesis, e.g., for synthesis of oximes. Commercialcially useful in cold weather. At 75 HAS, these comrade material is a wet, flaky solid C n a ni g f 3 to positions have from about 6.8% to about 12.0% by 8% by weight sulfuric acid, and about 0.1 to 3% water. weight sulfuric acid with a corresponding water content This product tends to set up to a hard cake during storage of from about 18.2% to about 13.0%, respectively. At and, when caked, it is difficult to break up again. Because 85% HAS, the sulfuric acid content is within a range of of the sulfuric acid content, HAS is corrosive to flesh from about 2.8% to about 5.5%. and ordinary steel and presents several problems in ship- Some specific compositions of this invention employping and handling. It has been customary to ship HAS in ing both commercial-grade and purified HAS are given fiber drums with an acid-resistant liner, but this procein Table 1.

TABLE 1.COMPOSITION OF SOME HAS COMPOSITIONS Crystallization temperature 20 C. or less 25 C. or less H1804, percent wt. H20, percent w't. H2SO4, percent wt. H2O, percent wt. Min. Max. Min. Max. Min. Max. Min. Max.

Commercial HAS (percent wt.):

75.0 7.2 12. 0 13. 0 17.8 6. 6 12. 5 12. 5 1s. 4 5. 5 7.5 12.5 14.5 4.5 8.1 11.9 15.5 5.0 6.6 10.9 12.5 4.2 7.3 10.2 13.3 3. 2 5. 5 11.8 9. 5 2. s 6. 2 s. s 12. 2

dure fails to avoid problems of caking and high shipping The HAS used in the practice of this invention can be costs. To avoid the caking problem it has been packaged roduced by any suitable process, several of which are in small lots in plastic bags which in turn are packaged known; i.e. those of Lippincott, US. Patents 2,113,812, in fiber drums. This method overco es he prob e of -813, -814, or Tryon, U.S. Patent 2,368,072. The sulfuric breaking P badly Caked material but lts in still higher acid content and water content are then adjusted as neccosts. essary to provide the composition of this invention se- It is an object of this invention to provide liquid coml d f shipment Positions of HASv In accordance with these processes, HAS is produced It is another object of this invention to provi C by reacting a nitroalkane, e.g., nitromethane, nitroethane, positions of HAS suitable for transportation in bulk conl-nitropropane, Z-nitropropane, or a mixture thereof, tainers. With 95% sulfuric acid, thereby producing a mixture 0011- Other objects of this invention will be apparent to sisting principally of HAS, a residue of the nitroalkane those skilled in the art from the description herein. molecule having the same number of carbon atoms as the It is the discovery of this invention that combinations nitroalkane, and XC u furi acid- The nitr alkane of HAS, sulfuric acid and water form low-melting eutecresidue is removed by distillation, and the resulting comtic mixtures and provide liquid compositions suitable for mercial-grade HAS-sulfuric acid residue is used in pretransportation in bulk containers, i.e., in tank cars and paring the compositions of this invention. If desired, tank trucks. The compositions of this invention are those the HAS can be further purified by any suitable means having an HAS content of from about to about and this purified HAS is also suitable for the practice of by weight and a sulfuric acid content Within the 70 this invention, but for reasons of economy the commerrange of from about 2.1% to about 12.5%. The remaincial grade is preferred.

der of these compositions is principally water along with In preparing the compositions of this invention, a predetermined amount of HAS is delivered to a suitable vessel, e.g., a stainless steel tank equipped with a stainless steel agitator. A predetermined amount of water and sulfuric acid sufiicient to provide a composition of this invention are then added to the HAS in the vessel and the mixture is thoroughly agitated until a homogeneous solution is obtained. Some heat is generated during the formation of the composition, but if desired, additional heat can be supplied to the mixture to accelerate the formation of the solution. The temperature is then preferably, but not necessarily lowered to about 60 C. The composition is then delivered to a tank car or tank truck for shipment. Optionally, the composition can be stored in an insulated storage vessel until needed for shipment.

If the composition has been allowed to cool, and if outside temperatures below the crystallization temperature of the composition are expected to be encountered during shipment, the temperature of the composition is raised to approximately 5060 C. before shipment.

The sulfuric acid which can be employed in the practice of this invention is preferably commercial grade having about 95% sulfuric acid content. The water employed in the practice of this invention is preferably of good quality having a minimum of residue. De-ionized water, steam condensate, and distilled water are examples of preferred grades of water.

The following examples are intended to illustrate this invention and are not to be construed as limitations thereof.

EXAMPLE 1 A lot of commercial grade hydroxylammonium acid sulfate had the following analysis:

Percent by weight Hydroxylammonium acid sulfate 92.2 Free sulfuric acid 4.5

Water 2.7 Organic acid (as propionic) 0.16

HAS g. HS g Water g Compositions 4-6 were prepared by adding the required amount of sulfuric acid and water to the HAS to give the proportions set forth below. The crystallization temperatures were as follows (the figures in parenthesis are interpolated values obtained from a plot of crystallization temperature versus sulfuric acid content):

Gomposi- Sulfuric acid, Crystallization tion No. percent wt. Water, percent wt. temperature, C.

3. 151. (10 2 15.3) 4. 5 .5 min. 5.?) 10. 0 16. 5 as; e2; e2; '7. 4 '7. s 34 11. 6 3. 4 53 EXAMPLE 2 Using the same lot of HAS as used for Example 1, another series of compositions at a concentration of 82.5% by weight HAS were prepared. The crystallization temperatures were as follows:

Composi- Sulfuric acid, Crystallization tion No. percent wt. Water, percent wt. temperature, C.

6. 0 11. 5 13.5 min.

The compositions having a sulfuric acid content within the range of from about 4.2% to about 7.3%, and a corresponding water content of from about 13.3% to about 10.2% had crystallization temperatures at or below about 25 C. and were determined to be suitable for shipment in tank cars or tank trucks. Compositions having from about 5.0% to about 6.6% sulfuric acid and a corresponding water content of from about 12.5% to about 10.9% had crystallization temperatures of about 20 C. or less and were determined to be especially useful for cold weather shipment.

EXAMPLE 3 The experiment of Example 2 was repeated except that the concentration of HAS was As in Example 1, compositions No. 1 and 2 were prepared by adding 3.8 g. hydroxylammonium sulfate and 11.68 g. of water, and 0.84 g. hydroxylammonium sulfate and 8.70 g. water, respectively, to each of two 50 g. portions of HAS. Compositions 3-6 were prepared by adding sulfuric acid and water to the HAS to give the proportions set forth below. The compositions had the following crystallization temperatures.

Composi- Sulfuric acid, Crystallization tion N 0. percent wt. Water, percent wt. temperature, C

The compositions having a sulfuric acid content Within the range of from about 4.5% to about 8.1%, and a corresponding Water content of from about 15.5% to about 11.9% had crystallization temperatures at or below about 25 C. and were determined to be suitable for shipment in tank cars or tank trucks. Compositions having from about 5.5% to about 7.5% sulfuric acid and a corresponding water content of from about 14.5% to about 12.5% had crystallization temperatures of about 20 C. or less and were determined to be especially useful for' cold weather shipment.

5 EXAMPLE 4 The experiment of Example 2 was repeated except that the concentration of HAS was 75%. As in Example 1, compositions No. 1 and 2 were prepared as follows:

No. HAS, g. HS, g. Water, g.

Compositions 3-9 were prepared by adding sulfuric acid and water as required to give the proportions set forth below. The compositions had the following crystallization temperatures.

Composi- Sulfuric acid, Crystallization tion N 0. percent wt. Water, percent wt. temperature, C.

(9. 3) (15. 7) (9.6 min.)

The compositions having a sulfuric acid content within the range of from about 6.6% to about 12.5%, and a corresponding water content of from about 18.4% to about 12.5% had crystallization temperatures at or below about 25 C. and were determined to be suitable for shipment in tank cars or tank trucks. Compositions having from about 7.2% to about 12.0% sulfuric acid and a corresponding water content of from about 17.8% to about 13.0% had crystallization temperatures of about C. or less and were determined to be especially useful for cold weather shipment.

EXAMPLE 5 Composi- Sulfuric acid, Crystallization tion No. percent wt. Water, percent wt. temperature, C.

1 2. 1 12. 9 25. 0 2 2. 6 12. 4 21. 9 3 (2. 8) (12. 2) (20.0) 4 3. 0 12. 0 18. 8 5 (3. 1) (l1. 9) (18.5 min.) 6 (3. 4) (11. 6) (20. 0) 7 3. 5 11. 5 20. 5 8 3. 8 11. 2 22. 1 9 (4. 4) (10. 6) 25. O 10 4. 6 10. 4 25. 9

The compositions having a sulfuric acid content within a range of from about 2.1% to about 4.4%, and a corresponding water content of from about 12.9% to about 10.6% had a crystallization temperature of about C. or less and were determined to be suitable for shipment in tank cars and tank trucks. Compositions having from about 2.8% to about 3.4% sulfuric acid and a corresponding water content of from about 12.2% to about 11.6% had crystallization temperatures of about 20 C. or less and were determined to be especially useful for cold weather shipment.

6 EXAMPLE 6 Following the general procedure of Example 5, six compositions were prepared, each having a concentration of 82.5% by weight of relatively pure HAS and having a free sulfuric acid content of from 3% to 6.5 the remainder being water. The compositions had the following crystallization temperatures.

Qomposi- Sulfuric acid, Water, Crystallization tion No. percent wt. percent wt. temperature, C.

3.0 14. 5 25.0 3. 5 14. 0 21. 5 3. 7 13. s 20. 0 (4. 2) (13. 3) (16.5 min. (5. 1) 12. 4 (20. 0) 5. 5 12. 0 20. 5 6.0 11.. 5 24. O (6. 4) 11. 1 (25. 0) 6. 5 11. 0 26.

The compositions having a sulfuric acid content within the range of from about 3.0% to about 6.4%, and a corresponding water content of from about 14.5% to about 11.1% had crystallization temperatures of about 25 C. or less and were determined to be suitable for shipment in tank cars and tank trucks. Compositions having from about 3.7% to about 5.1% sulfuric acid and a corresponding water content of from about 13.8% to about 12.4% had crystallization temperatures of about 20 C. or less and were determined to be especially useful for cold weather shipment.

EXAMPLE 7 Following the general procedure of Example 5, six compositions were prepared, each having a concentration of 80% by weight relatively pure HAS and a free sulfuric acid content of from 3.5% to 8%, the remainder being Water. The crystallization temperature of each composition Was as follows:

Composi- Sulfuric acid, Water, Crystallization tion No. percent wt. percent wt. temperature, C.

3. 5 16. 5 26. 0 (3. 7) (16. 3) (25.0) 4. 0 16. 0 22. (4. 4) (15. (20. 0) (5.0) (15.0) (15.6 min) (6. 3) 13. 7 20. 0

compositions having a sulfuric acid content within the range of from about 3.7% to about 7.8%, and a corresponding water content of from about 16.3% to about 12.2% had crystallization temperatures of about 25 C. or less and were determined to be suitable for shipment in tank cars and tank trucks. Compositions having from about 4.4% to about 6.3% sulfuric acid and a corresponding Water content of from about 15.6% to about 13.7% had crystallization temperatures of about 20 C. or less and were determined to be especially useful for cold weather shipment.

EXAMPLE 8 Following the general procedure of Example 5, six solutions were prepared, each having a concentration of by weight pure HAS and a free sulfuric acid of from 4% to 14%, the remainder being water. The crystallization temperature of each composition was as follows:

Composi- Sulfuric acid, Water, Crystallization tion N 0. percent wt. percent wt. temperature, C.

(9. O) (16. 0) (10.5 min.

The compositions having a sulfuric acid content within the range of from about 5.7% to about 11.7%, and a corresponding water content of from about 19.3% to about 13.3% had crystallization temperatures of about 25 C. or less and were determined to be suitable for shipment in tank cars and tank trucks. Compositions having from about 10.9% to about 6.8% sulfuric acid and a corresponding water content of from about 14.1% to about 18.2% had crystallization temperatures of about 20 C. or less and were determined to be especially useful for cold weather shipment.

Having described this invention, what is claimed is:

1. A liquid low-melting eutectic composition having a crystallization temperature of approximately 25 C. or

'less'consisting'essentially of hydroxylammonium acid sul- 2. The composition of claim 1 having a crystallization temperature of approximately 20 C., or less, having from about 75% to about 85% HAS and from within about 2.8% to about 12.0% sulfuric acid and water.

3. The composition of claim 1 having an HAS content of about 75 by weight and a sulfuric acid content within the range of from about 5.7% to about 12.5%.

4. The composition of claim 1 having an HAS content of abotu 85% by weight and a sulfuric acid content within the range of from about 2.1% to about 6.2% by weight.

5. The composition of claim 1 having an HAS content of about 80% by weight and a sulfuric acid content within the range of from about 3.7% to about 8.1% by weight.

6. The composition of claim 1 having an HAS content of baout 82.5% by weight and a sulfuric acid content within the range of from about 3.0% to about 7.3% by weight.

7. The composition of claim 2 having an HAS content of about by weight and a sulfuric acid content within the range of from about 6.8% to about 12.0% by Weight.

8. The composition of claim 2 having an HAS content of about by weight and a sulfuric acid content within the range of from about 4.4% to about 7.5% by weight.

9. The composition of claim 2 having an HAS content of about 82.5% by weight and a sulfuric acid content within the range of from about 3.7% to about 6.6% by Weight.

7 10. The" composition of claim 2 having an HAScona 1 a a tent of about 85.0% by Weight and a sulfuric acid content within the range of from about 2.8% to about 5.5% by weight.

References Cited Condensed Chemical Dictionary, Reinhold, 1961, 6th ed., p. 594.

Chemical Abstracts, American Chemical Society, vol. 5419, p. 17820f.

LEON D. ROSDOL, Primary Examiner I. GLUCK, Assistant Examiner U.S. Cl. X.R. 

